RESEARCH ARTICLE
Insecticidal Suppression of Asian Citrus Psyllid Diaphorina citri (Hemiptera: Liviidae) Vector of Huanglongbing Pathogens Jawwad A. Qureshi*, Barry C. Kostyk, Philip A. Stansly University of Florida, Entomology and Nematology Department, Institute of Food and Agricultural Sciences, Southwest Florida Research and Education Center, Immokalee, Florida, United States of America *
[email protected] Abstract OPEN ACCESS Citation: Qureshi JA, Kostyk BC, Stansly PA (2014) Insecticidal Suppression of Asian Citrus Psyllid Diaphorina citri (Hemiptera: Liviidae) Vector of Huanglongbing Pathogens. PLoS ONE 9(12): e112331. doi:10.1371/journal.pone.0112331 Editor: Kun Yan Zhu, Kansas State University, United States of America Received: March 20, 2014 Accepted: October 14, 2014 Published: December 1, 2014 Copyright: ß 2014 Qureshi et al. This is an openaccess article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability: The authors confirm that all data underlying the findings are fully available without restriction. All relevant data are provided in the paper. Funding: This research was supported by the Citrus Research and Development Foundation Inc., Florida. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: Funding by Citrus Research and Development Foundation Inc., does not alter the authors’ adherence to all the PLOS ONE policies on sharing data and materials.
Diaphorina citri vectors pathogens that cause ‘huanglongbing’ or citrus greening disease which poses a serious threat to citrus production worldwide. Vector suppression is critical to reduce disease spread. Efficacy is a main concern when choosing an insecticide. Insecticidal treatments of 49 products or 44 active ingredients (a.i) labeled or experimental were field tested between 2005–2013 as foliar sprays (250 treatments, 39 a.i) or soil applications (47 treatments, 9 a.i) to control D. citri in citrus. A combined effect of nymphal and adult suppression in response to sprays of 23 insecticides representing 9 modes of action (MoA) groups and 3 unknown MoA provided more than 90% reduction of adult D. citri over 24–68 days. Observable effects on nymphs were generally of shorter duration due to rapid maturation of flush. However, reduction of 76–100% nymphs or adults over 99–296 days was seen on young trees receiving drenches of the neonicotinoids imidacloprid, thiamethoxam or clothianidin (MoA 4A) and a novel anthranilic diamide, cyantraniliprole (MoA 28). Effective products identified for foliar sprays to control D. citri provide sufficient MoA groups for rotation to delay evolution of insecticide resistance by D. citri and other pests. However, cyantraniliprole is now the only available alternative for rotation with neonicotinoids in soil application to young trees. Sprays of up to eight of the most effective insecticides could be rotated over a year without repetition of any MoA and little or no recourse to neonicotinoids or cyantraniliprole, so important for protection of young trees. Other considerations effecting decisions of what and when to spray include prevalence of huanglongbing, pest pressure, pre-harvest intervals, overall budget, equipment availability, and conservation of beneficial arthropods. Examples of spray programs utilizing broad-spectrum and relatively selective insecticides are provided to
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Management of Diaphorina citri
improve vector management and may vary depending on individual or regional assessment of all factors.
Introduction Diaphorina citri Kuwayama, also known as Asian citrus psyllid (ACP), is a global pest of citrus and vector of ‘‘Candidatus Liberibacter’’ pathogens responsible for causing ‘huanglongbing’ (HLB) or citrus greening disease [1, 2, 3]. Huanglongbing is one of the world’s most devastating diseases of citrus, responsible for tree decline and loss of production in disease affected regions [4, 5]. In the United States, D. citri was first discovered in Palm Beach County, Florida on hedges of orange jasmine, Murraya paniculata (L.) Jack. (Rutaceae) in 1998 [6] and quickly established in citrus producing regions of the state [7, 8, 9]. First detection in the USA of the Asian form of HLB occurred in south Miami Dade during August 2005 [10]. The disease now occurs throughout the state and threatens a citrus industry which generates $9 billion in annual revenues [11, 12]. A recent study estimated that due to reduced citrus production in Florida, total cumulative production and revenue were reduced by 23% and 16%, respectively, and 48% of total jobs lost in the Agriculture, Forestry and Fisheries sector, over the five-year period since 2006 [13]. HLB was identified from Louisiana in 2008 and from South Carolina and Georgia in 2009 (http://www.aphis.usda.gov/ plant_health/plant_pest_info/) and is also present in Texas, Mississippi and California [14, 15]. New foliage growth (flush) regulates the dynamics of several citrus pests requiring soft tissues for oviposition and development including D. citri, citrus leafminer, Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae) and several aphid species. Flush production is influenced by weather, scion and rootstock variety and plant age [16]. Young trees flush frequently compared to mature trees and therefore need more protection from these pests. The typical pattern of shoot production in mature citrus trees in Florida begins with a major flush in late winter or early spring, a lesser flush in the early summer and minor flushes during late summer and fall, followed by a relatively dormant winter season in late fall and early winter with little or no new foliage growth [9, 17]. Reproduction of D. citri is totally dependent on availability of young shoots containing feather stage to recently expanded tender leaves. Female psyllids must feed on tender shoots to mature eggs and prefer opening buds and emerging shoots for oviposition. During the following 2–3 weeks, shoot and leaf tissues are still tender and are utilized by nymphs and adults respectively to complete development and mature eggs. Adults can also feed and survive on the fully developed leaves for several months [8, 18]. Complete control of HLB may not be feasible until plants expressing high levels of resistance to the vector and/or disease are available. Meanwhile, an integrated
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Management of Diaphorina citri
strategy involving biological and chemical control tactics is required for sustainable management of the pest to reduce disease spread. Biological control has always been an important component of citrus insect pest management in Florida [19] including D. citri. Lady beetles, lacewings and spiders are all wellknown as predators of citrus psyllids [18, 20, 21, 22, 23]. These and other predators were observed to inflict 80–100% mortality to D. citri immature and were abundant during spring and summer, though largely absent during winter in concert with citrus growth patterns and psyllid abundance [21, 22]. Two exotic Hymenopteran parasitoids of ACP, Diaphorencyrtis aligarhensis (Shafee, Alam and Agaral) (Encyrtidae) and Tamarixia radiata (Waterston) (Eulophidae) were introduced in Florida in 2000 [24]. Tamarixia radiata is now widely distributed in the Florida citrus ecosystem at variable rates of parasitism and new strains are being released to enhance parasitism rates, whereas D. aligarhensis has not yet established [9, 25]. Growers in Florida have also released the convergent lady beetle Hippodamia convergens Gue´rin-Me´neville from California; however, it is still not common there in citrus [26]. Although combined effects of natural enemies have not proven sufficient to prevent spread of HLB, nevertheless, conservation of these and other beneficial arthropods is essential for effective citrus pest management in Florida and elsewhere. Insecticides are presently a critical component of ACP management. The systemic neonicotinoid insecticides, thiamethoxam, imidacloprid and clothianidin and a new insecticide cyantraniliprole are allowed in Florida citrus but their use as soil applications is limited by rate restrictions to young trees [27]. Aldicarb (Temik 15 G) was used on large trees in Florida but is no longer permitted [18]. Suppression of ACP by sprays of broad-spectrum insecticides prior to flushing has proved to be an effective strategy for reducing populations. This is especially true of sprays during tree dormancy to target the overwintering adult population [23, 28]. Nevertheless, it is also necessary to control ACP during the growing season which in Florida commences with spring flush and lasts through mid-fall. The advent of HLB has greatly intensified insecticide use to control ACP in Florida citrus [29, 30]. However, timing, choice of products, and application methods during the growing season are far from standard. Factors such as overall budget, efficacy, pest pressure, equipment availability, conservation of beneficial insects and resistance management all warrant consideration. We have extensively field tested recommended and experimental insecticides in replicated experiments against ACP since 2005. This manuscript reports data on the effectiveness of the tested insecticides based on the number of days significantly fewer ACP were observed on the treated trees compared to the untreated control trees and degree of ACP reduction. The intent is to facilitate management decisions to treat citrus groves for ACP individually or on an area wide basis (www.flchma.org).
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Management of Diaphorina citri
Materials and Methods Study location and experimental trees Experiments were conducted at the Southwest Florida Research and Education Center, of the University of Florida-IFAS, Immokalee, FL, USA (Latitude: 26.484 N, Longitude: 81.435 W) and a neighboring commercial grove located near Labelle, FL, USA (Latitude: 26.693 N, Longitude: 81.446 W). No permit or specific permission was required. These studies did not involve endangered or protected species. Most tests for effects of foliar sprays on ACP were made on ‘Valencia’ sweet orange Citrus sinensis (L.) Osbeck (Rutaceae) trees planted in 1998 at a density of 326 trees/ha on double-row raised beds. Trees were pruned with hand held or tractor mounted hedger to encourage growth of new shoots to support ACP infestation. Soil applied insecticides were tested in 2–5 yr old orange trees flushing naturally. Trees were irrigated by micro sprinklers and subjected to conventional cultural practices [31]. There was little or no use of insecticides at the study locations. Psyllids in these experiments were feral and originated at locations where studies were conducted. Surrounding conventional groves employed chemical control to suppress psyllids.
Experimental design All experiments were designed as randomized complete blocks (RCB) with four replicates of each treatment. Four to 15 trees in a single row were used for each replicate of a treatment. Replicates within treated rows were separated from each other by one untreated tree and sprayed rows were separated from each other by an untreated buffer row to avoid spray drift between plots within and between treated rows. Testing was done during the growing season and young shoots required by psyllids to develop and reproduce were available either naturally or induced through pruning.
Treatment application Two hundred and ninety seven insecticidal treatments of 49 products or 44 active ingredients (a.i) (Table 1) representing 11 insecticide mode of action (MoA) (http://www.irac-online.org) groups and 8 unknown MoA were field tested as foliar sprays (250 treatments, 39 a.i) (Tables 2–4) and soil applications (47 treatments, 9 a.i) (Table 5) against ACP in citrus between 2005–2013. Rates tested were within the range recommended for use or being investigated for experimental use. Sprays were applied using a Durand Wayland 3P-10C-32 or John Bean 400 Redline air blast speed sprayer delivering between 935 and 1402 L/ha (100-150 gallon/acre) final application volume depending upon the requirement of the product. Certain low volume treatments were applied with a Proptec rotary atomizer sprayer which delivered between 47-94 L/ha (5–10 gallon/acre). Some insecticides were evaluated with an adjuvant, mostly horticultural mineral oil
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Management of Diaphorina citri
Table 1. Name, active ingredient, mode of action group and manufacturer of the products tested as foliar spray or soil application against Diaphorina citri. Producta
Active ingredient (% by weight)
IRAC MOA Groupb
Manufacturer
435 oil
horticultural mineral oil (98.8)
NA
Drexel Chemical Company, Memphis, TN
Actara 25 WG
thiamethoxam (25)
4A
Syngenta Crop Protection, LLC, Greensboro, NC
Admire Pro 4.6 SC
imidaclopridc (42.8)
4A
Bayer CropScience LP, Research Triangle Park, NC
Agri-Flex
abamectin + thiamethoxam (3+13.9)
6+4A
Syngenta Crop Protection, LLC, Greensboro, NC
Agri-Mek 0.15 EC
abamectinc (2)
6
Syngenta Crop Protection, LLC, Greensboro, NC
Apta 15 SC
tolfenpyrad (15)
21A
Nichino America Inc., Wilmington, DE
Assail 30 SG
acetamiprid (30)
4A
Cerexagri, Inc., King of Prussia, PA
Aza-Direct
azadirachtin (1.2)
NA
Gowan Company, Yuma, AZ
Belay 2.13 SC
clothianidin (23)
4A
Valent USA Corporation, Walnut Creek, CA
Beleaf 50 SG
flonicamid (50)
9C
FMC Corporation, Philadelphia, PA
Belt 4 SC
flubendiamide (39)
28
Bayer CropScience LP, Research Triangle Park, NC
Baythroid XL
beta-cyfluthrin (12.7)
3A
Bayer CropScience LP, Research Triangle Park, NC
Closer SC
sulfoxaflor (21.8)
4C
Dow AgroSciences, LLC, Indianapolis, IN
Danitol 2.4 EC
fenpropathrin (30.9)
3A
Valent USA Corporation, Walnut Creek, CA
Delegate WG
spinetoram (25)
5
Dow AgroSciences, LLC, Indianapolis, IN
Dibrom 8 E
naled (62)
1B
Amvac Chemical Corporation, Los Angeles, CA
Dimethoate 4 E
dimethoate (43.5)
1B
Cheminova, Inc., Wayne, NJ
Exirel
cyantraniliprole (10.2)
28
DuPont Company, Newark, DE
Entrust SC
spinosad (22.5)
5
Dow AgroSciences, LLC, Indianapolis, IN
Envidor 2 SC
spirodiclofen (22.3)
23
Bayer CropScience LP, Research Triangle Park, NC
Fulfill 50 WDG
pymetrozine (50)
9B
Syngenta Crop Protection, LLC, Greensboro, NC
Grandevo
Chromobacterium subtsugaec (30)
NA
Marrone Bio Innovations, Davis, CA
Imidan 70 W
phosmet (70)
1B
Gowan Company, Yuma, AZ
Lorsban 4 E
chlorpyrifosc (44.9)
1B
Dow AgroSciences, LLC, Indianapolis, IN
Magus
fenazaquin (18.8)
21A
Gowan Company, Yuma, AZ
Micromite 80 WGS
diflubenzuron (80)
15
Chemtura Corporation., Middlebury, CT
Movento 240 SC
spirotetramatc (22.4)
23
Bayer CropScience LP, Research Triangle Park, NC
MBI-206 EP
Burkholderia spp (NA)
NA
Marrone Bio Innovations, Davis, CA
M-Pede
potassium salts of fatty acids (49)
NA
Dow Agrosciences, LLC, Indianapolis, IN
MSR 2 E
oxydemeton-methyl (25)
1B
Gowan Company, Yuma, AZ
c
Mustang Max 1.5 EC
zeta-cypermethrin (9.6)
3A
FMC Corporation, Philadelphia, PA
Nexter
pyridaben (75)
21A
Gowan Company, Yuma, AZ
NNI0101-20SC
pyrifluquinazon (NA)
NA
Nichino America Inc., Wilmington, DE
NoFly WP
Isaria fumosoroseus strain FE 9901(18)
NA
Natural Industries Inc., Spring, TX
NUQ 05054
imidacloprid (NA)
4A
Nufarm Americas Inc., Burr Ridge, IL
Platinum 75 SG
thiamethoxamc (75)
4A
Syngenta Crop Protection, Greensboro, NC
Portal
fenpyroximate (5)
21A
Nichino America Inc., Wilmington, DE
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Management of Diaphorina citri
Table 1. Cont. Producta
Active ingredient (% by weight)
IRAC MOA Groupb
Requiem 25 EC
synthetic extract of Chenopodium ambrosioides (25)
NA
AgraQuest, Davis, CA
Sevin XLR
carbaryl (42.8)
1A
Bayer CropScience LP, Research Triangle Park, NC
Sil-Matrix
potassium silicate (29)
NA
PQ Corporation, Valley Forge, PA
Sivanto 200 SL
flupyradifurone (NA)
4D
Bayer CropScience LP, Research Triangle Park, NC
Manufacturer
Stallion
chlorpyrifos + zeta-cypermethrin (30.8+3.08)
1B+3A
FMC Corporation, Philadelphia, PA
Supracide 2 E
methidathion (24.4)
1B
Gowan Company, Yuma, AZ
Temik 15 G
aldicarb (15)
1A
Bayer CropScience LP, Research Triangle Park, NC
Venom 70 SG
dinotefuran (70)
4A
Valent Biosciences Corporation, Libertyville, IL
Verimark
cyantraniliprole (18.7)
28
DuPont Company, Newark, DE
VoliamFlexi
chlorantraniliprole + thiamethoxam (20+20)
28+4A
Syngenta Crop Protection, Greensboro, NC
Vydate L
oxamyl (24)
1A
DuPont Company, Newark, DE
Warrior II
lambda-cyhalothrin (22.8)
3A
Syngenta Crop Protection, Greensboro, NC
a
Not all products are permitted for use on orange, so always follow the label for details on proper use. Insecticide Resistance Action Committee (IRAC) Mode of Action (MOA) Scheme, Version 7.3, April 2014. cMore than one formulation or product brand tested. NA 5 Not available b
doi:10.1371/journal.pone.0112331.t001
(HMO). Without adjuvant comparisons are presented for insecticides evaluated at the same rate (Table 4). Soil drench application of systemic insecticides were made to bare soil at a radius of 61 cm (24 inches) around the trunk of the tree using an EZ-Dose sprayer operating at a pressure of 3.1 bar (45 psi) and flow rate of 14 L (3.7 gallon) per minute. Granular applications of Aldicarb were made by placing a weighed amount of product within two, 0.91 m (3 ft) furrows approximately 0.61 m (2 ft) from the base of the two opposing sides of tree. Furrows were covered with soil after application. NUQ 05054 is a slow release imidacloprid and was applied in a 1.22 m (4 ft) circle around the base of the tree.
Treatment evaluation ACP was sampled on 3 to 5 central trees in each sprayed plot (10 to 12 in soil drench plots). Adults were monitored by counting those falling on a clipboard covered with a 22628 cm (8K611 inch) laminated white sheet held horizontally under a randomly chosen branch which was then struck sharply three times with a PVC pipe to make a count for one ‘‘tap’’ sample [9, 33]. Four tap samples were conducted per tree. Adults on small trees in drench trials were counted visually. Ten randomly selected shoots per plot were collected and examined under a stereoscopic microscope in the laboratory to count number of ACP nymphs per shoot. Observations on adults and nymphs continued until significant differences with the untreated control were observed.
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18(10)
21(19) 5(5)
methidathion
fenpropathrin
fenpyroximate
naled
sulfoxaflor
spinetoram
Supracide 2 E
Danitol 2.4 EC
Portal
Dibrom 8 E
Closer SC
Delegate WG
PLOS ONE | DOI:10.1371/journal.pone.0112331 December 1, 2014 4(4) 5(0) 8(4) 24(22) 1(1)
abamectinb
zeta-cypermethrinb
chlorpyrifosb
fenazaquin
spirotetramat
chlorpyrifos + zeta-cypermethrin
Agri-Mek 0.15 EC
Mustang Max 1.5 EC
Lorsban 4 E
Magus
Movento 240 SC
Stallion
Chromobacterium subtsugaeb
phosmet
Burkholderia spp
horticultural mineral oil
Grandevo
Imidan 70 W
MBI-206 EP
435 oil
flubendiamide
diflubenzuron
Micromite 80 WGS
Belt 4 SC
9(5)
Admire Pro 4.6 SC
2(2)
11(0)
5(5)
7(0)
11(10)
10(9)
1(0)
potassium silicate
imidaclopridb
Sil-Matrix
7(7)
1(0)
abamectin + thiamethoxam
dimethoate
Agri-Flex
Dimethoate 4 E
16(15)
2(1)
10(7)
8(5)
1(0)
3(0)
3(0)
lamda-cyhalothrin
beta-cyfluthrin
Baythroid XL
10(4)
Warrior II
flupyradifurone
thiamethoxam
Sivanto 200 SL
Actara 25 WG
4(3)
chlorantraniliprole + thiamethoxam
VoliamFlexi
1(1) 8(8)
cyantraniliprole
tolfenpyrad
Nc
Exirel
Active ingredient
Apta 15 SC
Producta
5
192
192
8
24
3.1
1
128
11.8
5
16
24
4
4.3
16
8.5
4
2.9
16
24
16
32
3
1.4
2.8
6.8
5
11
16
Low
7.5
640
384
24
256
6.3
7
128
11.8
16
36
80
4.3
20
16
8.5
6
5.7
16
64
21.3
32
3
5.8
5.5
14
7.5
24
16
High
(oz/acre)
Rates tested
17
0
7
0
0
0
0
24
24
0
26
24
18
24
31
17
16
12
24
17
7
33
18
31
24
19
24
17
60
Low
17
38
28
33
28
48
67
24
24
58
42
42
44
42
31
53
52
67
42
58
60
33
51
42
60
52
67
68
60
High
17
18
18
18
20
20
22
24
24
26
28
29
30
31
31
31
32
32
33
33
33
33
35
35
36
37
46
57
60
0
4
4
6
2
6
8
0
0
4
4
3
5
4
0
6
2
4
9
4
6
0
10
4
4
3
12
6
0
¡ Mean SEM
(days)d
Duration of adult reduction
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
Ranke
36
0
48
0
0
0
0
74
100
0
58
79
44
32
96
82
66
17
52
59
68
91
62
88
58
47
82
77
80
Low
52
76
99
100
97
94
88
74
100
97
98
100
97
87
96
100
98
93
91
97
100
91
87
97
100
90
100
99
80
High
(%)d
44
36
69
51
64
46
60
74
100
60
66
91
75
54
96
92
89
62
71
76
90
91
79
92
84
73
90
90
80
6
10
9
18
8
9
9
0
0
6
11
4
9
13
0
4
2
7
19
5
4
0
9
3
5
3
4
3
0
¡ Mean SEM
Magnitude of reduction
Table 2. Duration and magnitude of reduction of Diaphorina citri adults on orange trees treated with foliar sprays of insecticides in Florida.
[34]
[34, 36, 37, 43, 44, 49, 50, 52, 54, 58, 63]
[45, 58, 63]
[40, 46, 52]
[45, 58, 63]
[34, 36, 39, 43, 49, 54]
[36, 37, 43, 51, 53, 56]
[50]
[52]
[34, 36, 37, 38, 41, 42, 44, 49, 51, 62]
[46, 57, 61]
[40, 48, 52, 57]
[41, 42, 48, 62]
[39, 43, 56]
[40]
[34, 44, 45, 56, 60]
[37, 38, 43, 48, 49, 50, 58 , 59, 63]
[38, 56, 59, 60]
[45, 57]
[34, 43, 45, 49, 55, 57, 61]
[38, 39, 40, 45, 46, 47, 48, 56]
[46]
[41, 42, 62]
[39, 40]
[39, 43, 44, 45, 56]
[37, 38, 56, 61, 62]
[45, 56, 60]
[34, 35, 55]
[56]
Referencef
Management of Diaphorina citri
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PLOS ONE | DOI:10.1371/journal.pone.0112331 December 1, 2014
spirodiclofen
pyrifluquinazon
Envidor 2 SC
NNI-0101
1(0)
1(0)
1(0)
1(0)
2(0)
5(1)
12(5)
2(0)
2(0)
3(0)
6.4
20
8
7
32
6.6
106
64
16
48
24
3
5.5
Low
6.4
20
8
7
64
10.6
393
192
32
48
48
3
5.5
High
(oz/acre)
Rates tested
0
0
0
0
7
0
0
0
16
14
0
16
17
Low
0
0
0
0
7
24
24
24
16
17
24
16
17
High
0
0
0
0
7
9
12
13
16
16
16
16
17
0
0
0
0
0
5
12
3
0
2
6
0
0
¡ Mean SEM
(days)d
Duration of adult reduction
42
41
40
39
38
37
36
35
34
33
32
31
30
Ranke
0
0
0
0
71
0
0
0
48
4
0
86
38
Low
0
0
0
0
79
100
97
76
53
74
59
86
38
High
(%)d
0
0
0
0
75
43
49
47
51
39
33
86
38
0
0
0
0
4
19
49
9
3
35
18
0
0
¡ Mean SEM
Magnitude of reduction
[35]
[36]
[46]
[53]
[47]
[36, 52, 57]
[34, 45]
[43, 47, 49, 50, 54]
[63]
[51, 54]
[36, 43]
[63]
[60]
Referencef
doi:10.1371/journal.pone.0112331.t002
b
Not all products are permitted for use on orange, so always follow the label for details on proper use. More than one formulation or product brand tested. c Number of times product was tested (in parenthesis with adjuvants) in a randomized complete block design using at least 20 trees in four replicates each time. d Significantly more reduction compared to untreated control (P,0.05). e Based on mean number of days significantly fewer adults were observed on treated trees compared to untreated trees. f Reference to reports which appeared in non-peer reviewed literature.
a
azadirachtin
pyridaben
Nexter
Aza-Direct
potassium salts of fatty acids 2(2)
M-pede
oxamyl
Chenopodium ambrosioides
Requiem 25 EC
acetamiprid
Isaria fumosoroseus
NoFly WP
Assail 30 SG
carbaryl
Sevin XLR
Vydate L
oxydemeton-methyl
MSR 2 E
1(1) 1(1)
pymetrozine
spinosad
Fulfill 50 WDG
Nc
Entrust SC
Active ingredient
Producta
Table 2. Cont.
Management of Diaphorina citri
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PLOS ONE | DOI:10.1371/journal.pone.0112331 December 1, 2014
spinetoram
pyridaben
dimethoate
Chromobacterium subtsugaeb
fenpyroximate
Burkholderia spp
flubendiamide
Nexter
Dimethoate 4 E
Grandevo
Portal
MBI-206 EP
Belt 4 SC
fenpropathrin
Danitol 2.4 EC
Delegate WG
abamectin + thiamethoxam
Agri-Flex
lamda-cyhalothrin
chlorantraniliprole + thiamethoxam
VoliamFlexi
thiamethoxam
spirotetramat
Movento 240 SC
Actara 25 WG
naled
Dibrom 8 E
Warrior II
5(5)
zeta-cypermethrinb
Mustang Max 1.5 EC
fenazaquin
4(3)
chlorpyrifos + zeta-cypermethrin
Stallion
flupyradifurone
5(0)
sulfoxaflor
Closer SC
Sivanto 200 SL
4
1(1)
tolfenpyrad
Apta 15 SC
Magus
16(1- 2.9 5) 11.8
8(4)
cyantraniliprole
Exirel
24
16
11
16
16
16
1.4
8
6.6
2(2)
5(5)
5
192
10(7) 24
11(1- 24 0)
1(0)
5(1)
21(1- 4 9)
3(0)
10(4) 2.8
18(1- 6.8 0)
7(7)
8(5)
8.5
5
24(2- 5 2)
2(1)
8(8)
1(1)
chlorpyrifosb
3 8
Lorsban 4 E
3(0) 7(0)
beta-cyfluthrin
phosmet
Low
Baythroid XL
Nc
7.5
384
64
256
8
10.6
6
5.8
5.5
14
36
21.3
8.5
7.5
16
16
4.3
11.8
5.7
24
16
80
24
3
High
(oz/acre)
Rates tested
Imidan 70 W
Active ingredient
Producta
10
7
0
0
17
0
3
17
3
10
12
7
17
17
0
21
15
24
6
17
24
17
17
15
Low
17
24
24
24
17
24
28
20
24
33
28
42
24
24
51
24
51
24
33
30
24
38
38
51
High
(days)
d
14
14
15
16
17
18
18
18
18
19
19
22
22
22
23
23
23
24
24
24
24
27
27
30
Mean
3
3
3
3
0
5
2
1
3
2
3
4
1
2
3
2
7
0
2
2
0
3
3
11
¡ SEM
Duration of nymphal reduction
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
Ranke
46
56
0
0
96
0
78
91
61
61
63
78
85
91
59
62
17
72
48
75
75
74
73
63
Low
67
89
98
92
96
62
98
99
99
99
97
93
99
99
99
87
99
72
95
98
75
98
100
84
High
(%)d
57
72
66
58
96
31
92
96
89
87
70
86
94
97
82
74
70
72
78
92
75
84
87
73
Mean
Magnitude of reduction
8
7
7
8
0
13
1
3
4
3
11
2
3
2
3
13
14
0
3
3
0
3
3
6
¡ SEM
Table 3. Duration and magnitude of reduction of Diaphorina citri nymphs on orange trees treated with foliar sprays of insecticides in Florida.
[34]
[45, 58, 63]
[34, 43, 45, 49, 55, 57, 61]
[45, 58, 63]
[40]
[36, 52, 57]
[37, 38, 43, 48, 49, 50, 5 8, 59, 63]
[39, 40]
[39, 43, 44, 45, 56]
[36, 37, 38, 56, 61, 62]
[46, 57, 61]
[38, 39, 40, 45, 46, 47, 48, 56]
[34, 44, 45, 56, 60]
[45, 56, 60]
[34, 36, 37, 38, 41, 42, 44, 49, 51, 62]
[45, 57]
[41, 42, 48, 62]
[52]
[38, 56, 59, 60]
[34, 35, 55]
[56]
[40, 48, 52, 57]
[40, 46, 52]
[41, 42, 62]
Referencef
Management of Diaphorina citri
9 / 22
PLOS ONE | DOI:10.1371/journal.pone.0112331 December 1, 2014
NNI-0101
1
32
1(0)
1(0)
2(0)
1(0)
1(0)
3(0)
6.4
8
48
20
7
16
24
12(5) 64
2(0)
11(0) 192
6.4
8
48
20
7
32
48
192
64
640
6.3
7
128
20
393
5.5
32
3
High
0
0
0
3
3
3
3
0
7
0
0
3
10
0
0
12
12
13
Low
0
0
3
3
3
7
10
17
7
24
27
17
10
20
24
12
12
13
High
(days)
d
0
0
2
3
3
5
5
6
7
9
10
10
10
10
12
12
12
13
Mean
0
0
2
0
0
2
2
2
0
3
4
2
0
5
12
0
0
0
¡ SEM
Duration of nymphal reduction
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
Ranke
0
0
0
43
40
0
53
0
59
0
0
44
67
0
0
66
77
63
Low
0
0
90
43
40
40
96
78
72
78
87
94
67
84
90
66
77
63
High
(%)d
0
0
45
43
40
20
69
35
65
50
44
73
67
59
45
66
77
63
Mean
Magnitude of reduction
0
0
45
0
0
20
14
9
6
9
12
6
0
20
45
0
0
0
¡ SEM
[35]
[46]
[51, 54]
[36]
[53]
[63]
[36, 43]
[43, 47, 49, 50, 54]
[47]
[34, 36, 37, 43, 44, 49, 50, 52, 54, 58, 63]
[34, 36, 39, 43, 49, 54]
[36, 37, 43, 51, 53, 56]
[50]
[39, 43, 56]
[34, 45]
[60]
[46]
[63]
Referencef
doi:10.1371/journal.pone.0112331.t003
b
Not all products are permitted for use on orange, so always follow the label for details on proper use. More than one formulation or product brand tested. c Number of times product was tested (in parenthesis with adjuvants) in a randomized complete block design using at least 20 trees in four replicates each time. d Significantly more reduction compared to untreated control (P,0.05). e Based on mean number of days significantly fewer nymphs were observed on treated trees compared to untreated trees. f Reference to reports which appeared in non-peer reviewed literature.
a
azadirachtin
pyrifluquinazon
Aza-Direct
Isaria fumosoro- 2(0) seus
NoFly WP
carbaryl
oxydemetonmethyl
MSR 2 E
Sevin XLR
Chenopodium ambrosioides
Requiem 25 EC
acetamiprid
oxamyl
Vydate L
spirodiclofen
horticultural mineral oil
435 oil
Envidor 2 SC
diflubenzuron
Micromite 80 WGS
Assail 30 SG
9(5)
imidaclopridb
Admire Pro 4.6 SC
128
4.3
106
5.5
32
3
Low
(oz/acre)
Rates tested
10(9) 3.1
4(4) 1(0)
2(2)
1(1)
potassium silicate
potassium salts of fatty acids
M-pede
Sil-Matrix
pymetrozine
Fulfill 50 WDG
1(0)
1(1)
Nc
Agri-Mek 0.15 EC abamectinb
spinosad
methidathion
Entrust SC
Active ingredient
Supracide 2 E
Producta
Table 3. Cont.
Management of Diaphorina citri
10 / 22
PLOS ONE | DOI:10.1371/journal.pone.0112331 December 1, 2014 64
spinetoram
chlorpyrifos
diflubenzuron
Chenopodium ambrosioides
Lorsban 4 E
Micromite 80 WGS
Requiem 25 EC
fenpropathrin
Danitol 2.4 EC
Delegate WG
thiamethoxam
Actara 25 WG
sulfoxaflor
flupyradifurone
Sivanto 200 SL
Closer SC
64
Chenopodium ambrosioides
Requiem 25 EC
fenpyroximate
diflubenzuron
Micromite 80 WGS
naled
chlorpyrifos
Lorsban 4 E
Portal
spinetoram
Delegate WG
Dibrom 8 E
16
sulfoxaflor
Closer SC
96
6.3
40
4
2.9
16
5.5
7
96
6.3
40
4
2.9
16
fenpyroximate
naled
Portal
Dibrom 8 E
21
17
17
24
10
33
24
10
33
22
21
ACP Nymph
24
17
24
24
19
24
24
40
36
21
10
0
17
10
33
21
10
17
22
14
24
3
24
17
12
42
24
31
36
58¡16
67¡07
78¡14
74¡11
100¡00
83¡10
87¡08
43¡08
88¡04
97¡07
80¡05
76¡06
94¡03
79¡00
96¡02
88¡08
91¡16
61¡09
92¡03
96¡08
60¡20
66¡08
0
98¡02
96¡01
71¡12
62¡14
48¡20
88¡05
90¡02
92¡03
63¡17
47¡00
99¡01
98¡02
74¡14
52¡12
59¡12
83¡10
84¡05
[50]
[34, 43]
[48, 52]
[48]
[38]
[45, 57]
[43]
[38, 40]
[44]
[61]
[50]
[34, 43]
[48, 52]
[48]
[38]
[45, 57]
[43]
[38, 40]
[44]
[61]
Referencec
doi:10.1371/journal.pone.0112331.t004
b
Not all products are permitted for use on orange, so always follow the label for details on proper use including adjuvants. Significantly more reduction compared to untreated control (P,0.05). Duration of reduction is one number representing days significantly fewer D. citri were observed on treated trees compared to untreated trees. Magnitude of reduction is mean ¡ SEM calculated from reduction observed on multiple dates until significant effect was observed. c Reference to reports which appeared in non-peer reviewed literature.
a
16
fenpropathrin
Danitol 2.4 EC
7 5.5
flupyradifurone
thiamethoxam
Sivanto 200 SL
ACP Adult
Without adjuvant
With adjuvant
With adjuvant
(oz/acre)
Without adjuvant
Magnitude of reduction (%)b
Duration of significant reduction (days)b
Product rate
Actara 25 WG
Active ingredient
Producta
Table 4. Duration and magnitude of reduction of Diaphorina citri adults and nymphs on orange trees sprayed with same rate of an insecticide alone or with horticultural mineral oil at 23% of application volume.
Management of Diaphorina citri
11 / 22
Management of Diaphorina citri
Statistical analysis Each test was conducted using 4 replicates for treatment and control so that the probability of detecting treatment effects could be evaluated with confidence. Data were subjected to analysis of variance (ANOVA) to evaluate treatment effects on ACP and means separated using Least Significant Difference (LSD) test contingent on a significant F for treatment effect (P50.05) [32]. Active ingredients were ranked by the number of days significantly fewer ACP nymphs or adults were observed on treated trees compared to untreated controls (P,0.05). Means averaged over all trials for each active ingredient are presented with standard error.
Results Effects of foliar sprays of insecticides on Diaphorina citri adults Thirty eight of the 42 products tested significantly suppressed adults (P,0.05) compared to untreated control (Table 2). A mean reduction of 90–100% in adult psyllids over 24–57 days (3–8 weeks) compared to untreated control was observed with foliar sprays of tolfenpyrad (Apta 15 SC), chlorantraniliprole + thiamethoxam (VoliamFlexi), lamda-cyhalothrin (Warrior II), methidathion (Supracide 2 E), fenpropathrin (Danitol 2.4 EC), abamectin + thiamethoxam (Agri-Flex), dimethoate (Dimethoate 4 E), chlorpyrifos (Lorsban 4 E) and chlorpyrifos + zeta-cypermethrin (Stallion). Reduction with the high rates of the above products and flupyradifurone (Sivanto 200 SL), thiamethoxam (Actara 25 WG), fenpyroximate (Portal), naled (Dibrom 8 E), sulfoxaflor (Closer SC), spinetoram (Delegate WG), zeta-cypermethrin (Mustang Max 1.5 EC), fenazaquin (Magus), spirotetramat (Movento 240 SC), diflubenzuron (Micromite 80 WGS), Chromobacterium subtsugae (Grandevo), phosmet (Imidan 70 W), Burkholderia spp (MBI-206 EP), potassium salts of fatty acids (M-Pede) and pyridaben (Nexter) also averaged 90% or more. Reduction averaged 38–88% over 16–67 day (2–9 week, Table 2) periods with high rates of chlorantraniliprole (Exirel), beta-cyfluthrin (Baythroid XL), abamectin (Agri-Mek 0.15 EC), potassium silicate (Sil-Matrix), imidacloprid (Admire Pro), 435 oil, flubendiamide (Belt 4 SC), pymetrozine (Fulfill 50WDG), spinosad (Entrust SC), oxydemeton-methyl (MSR 2 E), carbaryl (Sevin XLR), Isaria fumosoroseus (NoFly WP) and Chenopodium ambrosioides (Requiem 25 EC). Psyllid reduction associated with low rates was much less compared with high rates and never reached 90%. We did not observe apparent suppression of adults from acetamiprid (Assail 30 SG), azadirachtin (Aza-direct), spirodiclofen (Envidor 2 SC) or pyrifluquinazon (NNI0101-20SC). Application of some insecticides with HMO improved their performance against ACP (Table 4). Significant suppression of adults prolonged 7–14 days and improved 9–47% with the addition of an adjuvant to treatments of fenpropathrin (Danitol 2.4 EC), sulfoxaflor (Closer SC), spinetoram (Delegate WG) and
PLOS ONE | DOI:10.1371/journal.pone.0112331 December 1, 2014
12 / 22
Management of Diaphorina citri
diflubenzuron (Micromite 80 WGS). HMO by itself provided an average of 36% reduction in adults for 18 days (Table 2).
Effects of foliar sprays of insecticides on Diaphorina citri nymphs Forty of the 42 products provided some level of significant nymphal suppression (P,0.05, Table 3). More than 90% of mean reduction lasting 17–24 days was observed with tolfenpyrad (Apta 15 SC), chlorantraniliprole + thiamethoxam (VoliamFlexi), abamectin + thiamethoxam (Agri-Flex), lamda-cyhalothrin (Warrior II), spinetoram (Delegate WG), and dimethoate (Dimethoate 4 E). Similar levels of reduction were observed with high rates of these six products and phosmet (Imidan 70 W), sulfoxaflor (Closer SC), chlorpyrifos (Lorsban 4 E), zetacypermethrin (Mustang Max 1.5 EC), spirotetramat (Movento 240 SC), fenpropathrin (Danitol 2.4 EC), fenazaquin (Magus), flupyradifurone (Sivanto 200 SL), thiamethoxam (Actara 25 WG), Chromobacterium subtsugae (Grandevo), fenpyroximate (Portal), potassium salts of fatty acids (M-Pede), imidacloprid (Admire Pro), oxydemeton-methyl (MSR 2 E) and carabryl (Sevin XLR). From remaining 21 products 19 provided 40–89% reduction in nymphs at high rates. Psyllid reduction associated with low rates was much less compared with high rates and never reached 90% except for chlorantraniliprole + thiamethoxam (VoliamFlexi) and lamda-cyhalothrin (Warrior II). Only azadirachtin (Azadirect) and pyrifluquinazon (NNI0101-20SC) showed no activity against nymphs as with adults. Nymphal suppression prolonged 3–17 days and improved 1–78% by adding HMO to insecticidal sprays except fenpyroximate (Portal) (Table 4). HMO by itself provided an average of 50% reduction in nymphs for 9 days ( Table 3).
Effects of soil applications of insecticides on Diaphorina citri adults and nymphs Mean reduction (P,0.05) of 78–85% of adults over 81–111 days (12–16 weeks) and 71–89% of nymphs over 85–107 days (12–15 weeks) was observed with soil drenches of imidacloprid (Admire Pro 4.6 SC), thiamethoxam (Platinum 75 SG) and clothianidin (Belay 2.13 SC) applied to young trees (Table 5). Comparable reduction of both adults and nymphs was observed with the soil drenches of cyantraniliprole (Verimark). Up to 100% reduction lasting 245–296 days in nymphs was observed with Verimark, Admire Pro 4.6 SC and Platinum 75 SG. A slow release granular formulation of imidacloprid (NUQ 05054) lasted longer than liquid formulations. Aldicarb (Temik 15 G) was less effective than imidacloprid and cyantraniliprole but provided greater suppression compared to dinotefuran (Venom 70 SG), flupyradifurone (Sivanto 200 SL) and spirotetramat (Movento MPC), both in duration and magnitude. Flonicamid (Beleaf 50 SG) was the least effective insecticide tested as a drench although it also showed activity. Psyllid reduction associated with low rates was much less compared with high rates.
PLOS ONE | DOI:10.1371/journal.pone.0112331 December 1, 2014
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Management of Diaphorina citri
Table 5. Duration and magnitude of reduction of Diaphorina citri adults and nymphs on orange trees treated with soil applications of insecticides in Florida. Producta
Rates tested (oz/acre) Duration of reduction (days)f
Active ingredient Ne
Low
High
Low
High
Mean
¡ SEM
Magnitude of reduction (%)f Rankg
Low
High
Mean
¡SEM
Referenceh
ACP adult NUQ 05054b
imidacloprid
2
160
160
176
176
176
0
1
71
71
71
0
[66, 67]
Verimarkc
cyantraniliprole
7
10.3
30.4
140
140
140
0
2
51
76
60
8
[64, 65, 68]
4
6
12
44
140
111
23
3
68
85
78
4
[68, 75]
Belay 2.13 SCc clothianidin b
Temik 15 G
aldicarb
Admire Pro 4.6 imidacloprid SCc
thiamethoxamd
Platinum 75 SGc
3
125
528
92
121
106
8
4
68
81
75
4
[66, 73]
12
4.7
16
37
153
84
14
5
50
94
79
5
[64, 6 5, 66, 67, 68, 69, 70, 71, 72, 74, 75]
7
2.7
18.8
43
99
81
13
6
65
95
85
7
[64, 6 5, 69, 70, 71]
Venom 70 SGc dinotefuran
2
3
3.8
37
55
46
9
7
28
56
42
14
[69, 75]
Sivanto 200 SLc
6
14
28
0
62
43
9
8
0
81
47
12
[72, 74]
Movento MPCc spirotetramat
2
8
16
0
42
21
21
9
0
78
39
39
[74]
Beleaf 50 SGc
3
6.3
20.8
0
37
20
11
10
0
46
18
14
[75]
flupyradifurone
flonicamid
ACP nymph Verimarkc
cyantraniliprole
7
10.3
30.4
70
296
185
38
1
73
100
84
4
[64, 65, 68]
NUQ 05054b
imidacloprid
2
160
160
142
223
183
41
2
42
45
44
2
[66, 67]
12
4.7
16
44
245
107
18
3
40
100
71
6
[64, 6 5, 66, 67, 68, 69, 70, 71, 72, 74, 75]
7
2.7
18.8
43
274
103
29
4
60
100
85
6
[64, 65, 69, 70, 71]
Belay 2.13 SCc clothianidin
4
6
12
44
141
85
20
5
81
93
89
3
[68, 75]
Temik 15 Gb
3
125
528
23
121
72
49
6
17
55
36
19
[66, 73]
Admire Pro 4.6 imidacloprid SCc
thiamethoxamd
Platinum 75 SGc
Venom 70 SG
aldicarb c
dinotefuran
2
3
3.8
30
84
57
27
7
24
51
38
14
[69, 75]
Sivanto 200 SLc
flupyradifurone
6
14
28
0
55
32
8
8
0
65
41
11
[72, 74]
Beleaf 50 SGc
flonicamid
3
6.3
20.8
0
37
25
12
9
0
28
17
9
[75]
2
8
16
0
0
0
0
10
0
0
0
0
[74]
Movento MPCc spirotetramat a
Not all products are permitted for use on orange, so always follow the label for details on proper use. Granular formulations, aldicarb applied within two, 3 ft furrows approximately 2 ft from the base of the two opposing sides of tree. NUQ 05054 is a slow release imidacloprid applied in a 4 ft circle around the base of the tree. c Liquid formulations applied as drenches to bare soil at a radius of 24 inches around the trunk of the tree with an EZ-Dose sprayer at a pressure of 45 psi and a flow rate of 3.7 gallon per minute. d More than one formulation tested. e Number of times product was tested in a randomized complete block design using at least 20 trees in four replicates each time. f Significantly more reduction compared to untreated control (P,0.05). g Based on mean number of days significantly fewer adults or nymphs were observed on treated trees compared to untreated trees. h Reference to reports which appeared in non-peer reviewed literature. b
doi:10.1371/journal.pone.0112331.t005
PLOS ONE | DOI:10.1371/journal.pone.0112331 December 1, 2014
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Discussion Insecticides are the most important component of ACP management available to reduce the spread and severity of HLB. Therefore, repeated field evaluations of multiple products against ACP are needed to provide growers with a range of effective products with different MoA that can be rotated to suppress ACP and delay the evolution of insecticide resistance. We observed that sprays of 23 products including new additions tolfenpyrad, cyantraniliprole, flupyradifurone and sulfoxaflor representing 9 known IRAC MoAs and 3 unknown MoAs provided more than 90% reduction in psyllid populations. Tolfenpyrad, cyantraniliprole and flupyradifurone provided more ACP reduction than sulfoxaflor and were comparable to previously registered insecticides both in duration and magnitude of psyllid reduction. Tolfenpyrad, cyantraniliprole and sulfoxaflor are now registered for use against ACP in the USA. Cyantraniliprole is a second-generation anthranilic diamide insecticide MoA group 28 responsible for activating ryanodine receptors and negatively impacting muscle functions. Significant reduction in the ACP with cyantraniliprole compared to a commonly used pyrethroid fenpropathrin (Danitol 2.4 EC) was also observed in the laboratory and field in another study [76]. Tolfenpyrad is classified as MoA group 21A as is fenazaquin, fenpyroximate and pyridaben. Sulfoxaflor and flupyradifurone belong to MoA groups 4C and 4D respectively, thus different sub groups than other (4A) neonicontinoids. Flupyradifurone (Sivanto) is from the butenolide chemical class, containing a bioactive scaffold originally isolated from the plant Stemona japonica. Premixes Agri-Flex (abamectin 3% + thiamethoxam 13.9%) and VoliamFlexi (chlorantraniliprole 20% + thiamethoxam 20%) showed comparable effectiveness, but with the disadvantage of removing two modes of action from rotation. These new and promising insecticides along with several already registered products which showed high levels of effectiveness against ACP will broaden the range of products available to control this pest. Others that have shown activity against sucking pests and citrus leafminer may also prove effective [35, 38, 77, 78]. Although the number of times a product was tested varied from 1 to 24, each test was conducted rigorously using 4 replicates for treatment and control so that the probability of detecting treatment effects could be evaluated with confidence. Obviously, more tests would warrant even greater confidence in the result. Generally, findings on effective products were similar when tested multiple times, and in some cases were also confirmed in studies by others. Application of insecticides with HMO as adjuvant generally improved their effect against ACP. The petroleum based HMO, itself formulated with a surfactant, is a commonly used adjuvant which, when applied alone, also provided considerable protection from ACP (Table 2,3). Insecticides approved by Organic Management Research Institute (OMRI) such as petroleum based HMO (435 oil), potassium salts of fatty acids (M-Pede), potassium silicate (Sil-Matrix) (mineral product), spinosad (Entrust SC) and Chromobacterium subtsugae (Grandevo) (bacterial cultures or extracts) provided
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an average of only two weeks of control. However, 74–97% suppression was seen at high rate which is comparable to standard synthetic insecticides. While the effectiveness of these products tended to be short-lived, they could still be useful for rotation with synthetic insecticides to reduce selection for insecticide resistance in psyllids, conserve natural enemies, for application on blooming citrus for which few synthetic products are allowed, and in organic groves that prohibit synthetic products [45, 79]. Frequent applications of such insecticides during the growing season may be an option compatible with biological control. Most foliar sprays appeared to suppress adults longer than nymphs with the exceptions of acetamiprid (Assail 30 SG), spirodiclofen (Envidor 2 SC), phosmet (Imidan 70 W) and pyridaben (Nexter). This may largely be due to the short (3week) duration of shoot suitability for oviposition and subsequent nymphal development, after which there is little or no new flush that has been sprayed. Thus, direct effects on nymphs are measurable for only the 2–3 weeks it takes for new shoots to harden and for nymphs to mature to adulthood. Later effects on adults and subsequently nymphal populations are probably carryovers from earlier suppression. Several products such as 435 oil, imidacloprid (Admire Pro), acetamiprid (Assail 30 SG), flubendiamide (Belt 4 SC), sulfoxaflor (Closer SC), spirodiclofen (Envidor 2 SC), pymetrozine (Fulfill 50WDG), phosmet (Imidan 70 W), spirotetramat (Movento 240 SC), oxydemeton-methyl (MSR 2 E) and flupyradifurone (Sivanto 200 SL) provided 13–43% more reduction of nymphs than adults. However, most young nymphs are protected inside the newly developing unfolded leaves where ACP oviposit, therefore some avoid contact with the spray. These residual populations along with some left over adults are usually enough to initiate a new generation that may require additional treatment. Diaphorina citri populations respond rapidly to selection pressures due to high fecundity and short generation times, so any insecticide application selects for resistance. Some degree of resistance to key insecticides has already been documented in ACP populations in Florida [76]. Therefore, it is prudent to use a particular MoA only once a year. There is no ‘‘fits all’’ spray program that will satisfy every grower’s needs in regard to cost, efficacy against ACP and other pests, conservation of beneficial insects and resistance management. Example programs based on number of sprays per year using currently registered products are given in Table 6 to illustrate how these criteria could be used, contingent on actual pest populations and individual or regional assessment of all factors. Young trees flush often and are best protected with soil drenches or possibly injections of systemic insecticides. In the past, the neonicotinoids imidacloprid, thiamethoxam, and clothianidin were the only effective systemic insecticides allowed in Florida citrus for drench application, providing extended protection against ACP and, to a lesser extent, citrus leafminer. However, all shared the same 4A MoA and therefore could only be rotated with sprays of different MoA to slow selection for pesticide resistance. Cyantraniliprole (MoA 28) has been shown to provide significant reduction of ACP as well as citrus leafminer as a drench comparable to the neonicotinoid insecticides [64, 65] and can thus serve as a rotation partner to slow the evolution of insecticide resistance in ACP and other pests.
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Table 6. Example insecticide spray programs for Diaphorina citri considering other pests in Florida citrus. Insecticide sprays per year (excluding frequent applications of 435 oil alone) Month
One
Two
Four
Five
Seven
Other pests controlled
MOAc Group
Jan
Pyrethroid
Pyrethroid
Pyrethroid
Pyrethroid
Pyrethroid
weevils
3
Moventoa,b
Moventoa,b
Moventoa,b
rust mites, scales, mealybugs
23
Portalb
spider mites, rust mites
21A
Closer
aphids, mealy- 4C bugs leafminer, rust mites
NA
leafminer
5
leafminer, rust mites
6 or 4+6
Feb
Mar
Apr
435 Oil
435 Oil
435 Oil
435 Oil
435 Oil
May
435 Oil
435 Oil
Delegatea
Delegatea
Delegatea
a
a
Jun Jul
435 Oil
435 Oil
a,b
Delegate
Delegate
Agri-Mek Flexa,b
or Agri-
435 Oil
435 Oil
435 Oil
leaf miner, rust NA mites
Micromitea,b
Micromitea,b
leafminer, rust mites, weevils
15
Organophosphate
Organophosphate
weevils
1B
Aug Sep Oct Nov-Dec
Organophosphate
Organophosphate
a c
Generally applied with oil or another surfactant. b Primarily for control of nymphs. Insecticide Resistance Action Committee (IRAC) Mode of Action (MOA) group, http://www.irac-online.org, NA 5 Not available.
doi:10.1371/journal.pone.0112331.t006
Growers and managers often work with annual budgets based on anticipated needs and profits. Nevertheless, some flexibility is desirable to account for changes in the actual disease, pest or price situation. Research has shown that 4–7 sprays targeting ACP in citrus orchards with close to 100% HLB incidence significantly increased yields, but were not always cost effective when combined with foliar nutrient sprays to mitigate effects of HLB [80]. Slowing spread of HLB under low incidence conditions would have more far reaching implications but has not be quantitatively evaluated in the US, although aggressive vector control coupled with rogueing of symptomatic trees is purported to be successful on large citrus plantations in Brazil [81]. A further consideration is the effect of resident ACP populations on the sustainability of new citrus plantings in the face of HLB for which economic analysis is not yet forthcoming. At least one and preferably two aerial or ground applications of broadspectrum insecticides during the ‘‘dormant’’ (winter) season when most mature trees are not flushing has been shown to provide significant reduction in ACP and need for insecticides into growing season as well as conserving biological control [22, 23, 82]. However, timing of insecticide application, choice of products, and application methods during the growing season are far from standard, given the plethora of factors mentioned above. Several commonly use insecticides were
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shown to negatively impact predators and parasitoids of ACP in the laboratory and field experiments [33, 83, 84]. Effective use of selective insecticides such as soil-applied systemic insecticides, horticultural mineral oils, lipid synthesis inhibitors and spinosyns can be integrated with sprays of less selective chemistries to reduce ACP populations, risk of pest resistance to insecticides and incidence of HLB. Additional sprays during the growing season could be based on scouting and targeted at adults prior to anticipated new growth to ensure that new growth is protected from infestation. Our intention here is to furnish a starting point for planning a management program for ACP and other citrus pests. Efficacy is only one, albeit an important consideration in the decision of what insecticide to apply. Grower experience and additional field testing will provide more information on these and new products not presently available. Applications made to larger areas of commercial citrus using an area-wide approach appear to have provided extended suppression by avoiding re-colonization of treated groves from surrounding untreated habitats (www.flchma.org), although other factors of scale, environmental or biological conditions and insecticide resistance may influence outcomes. Some low levels of resistance against imidacloprid, chlorpyriphos, thiamethoxam, malathion and fenpropathrin have been reported [76]. It is possible that there were some resistant populations at the study locations. The high level of suppression (90-100%) observed over 24-68 days with sprays of 24 insecticides and even longer with soil applied insecticides indicate that resistance levels, if any, were probably low. However, insecticide resistance may become a serious problem for future ACP control, given the increasing intensity of use. Therefore, individual and area-wide management programs need to consider proper pest monitoring and rotation of insecticide MoA. Extensive monitoring for field resistance is also warranted and already initiated in Florida and elsewhere.
Acknowledgments We would like to thank Benny Pena, Robert Reifer, Joel Mendez, Zachary Lahey, Ted Stansly, Miriam Ortez, Mauricio Pinto, Cameron Brennan, Miguel Rua, Monica Trianna, Kat Perez and Matt Conley for technical assistance and manufactures and suppliers of tested products.
Author Contributions Conceived and designed the experiments: PAS JAQ BCK. Performed the experiments: BCK JAQ PAS. Analyzed the data: JAQ BCK PAS. Contributed reagents/materials/analysis tools: PAS BCK JAQ. Wrote the paper: JAQ PAS.
References 1. Garnier M, Jagoueix-Eveillard S, Cornje HF, Le Roux PR, Bove´ JM (2000) Genomic characterization of a Liberibacter present in an ornamental rutaceous tree, Calodendrum capense, in the Western Cape
PLOS ONE | DOI:10.1371/journal.pone.0112331
December 1, 2014
18 / 22
Management of Diaphorina citri
province of South Africa. Proposal of ‘Candidatus Liberibacter africanus subsp. capensis’. Int J Syst Evol Microbiol 50: 2119–2125. 2. Halbert SE, Manjunath KL (2004) Asian citrus psyllids (Sternorrhyncha: Psyllidae) and greening disease of citrus: a literature review and assessment of risk in Florida. Fla Entomol 87: 330–353. 3. Grafton-Cardwell B, Stelinski LL, Stansly PA (2013) Biology and management of Asian citrus psyllid, vector of huanglongbing pathogens. Annu. Rev. Entomol. 58: 413–432. 4. Roistacher CN (1996) The economics of living with citrus diseases: huanglongbing (greening) in Thailand, in Proc 13th Conf of International Organization of Citrus Virologists (IOCV), ed., by da Gra¸ca JV, Moreno P and Yokomi RK. University of California, Riverside, CA, pp., 279–285. 5. Bove´ JM (2006) Huanglongbing: a destructive, newly-emerging, century-old disease of citrus. J Plant Pathol 88: 7–37. 6. Halbert SE (1998) Entomology section. Tri-ology 37:(May–June): 6–7. 7. Michaud JP (2002) Biological control of Asian citrus psyllid (Homoptera: Psyllidae) in Florida. A preliminary report. Entomol News 113: 216–222. 8. Tsai JH, Wang JJ, Liu YH (2002) Seasonal abundance of the Asian citrus psyllid, Diaphorina citri (Homoptera: Psyllidae) in southern Florida. Fla Entomol 85: 446–451. 9. Qureshi JA, Rogers ME, Hall DG, Stansly PA (2009) Incidence of invasive Diaphorina citri (Hemiptera: Psyllidae) and its introduced parasitoid Tamarixia radiata (Hymenoptera: Eulophidae) in Florida citrus. J Econ Entomol 102: 247–256. 10. Halbert SE (2005) Pest Alert: Citrus Greening/Huanglongbing. Florida Department of Agriculture and Consumer Services. Division of Plant Industry. Available: http://www.freshfromflorida.com/DivisionsOffices/Plant-Industry/Plant-Industry-Publications/Pest-Alerts/Pest-Alerts-Citrus-Greening. Accessed 2014 March 15. 11. National Agricultural Statistics Summary. Florida Agricultural Statistics 2011–22012. http://www.nass. usda.gov/Statistics_by_State/Florida/Publications/Citrus/fcs/2011-12/fcs1112.pdf. Accessed 2014 March 12. 12. (FDACS) (2013) Florida Department of Agriculture and Consumer Services, Division of Plant Industries, Huanglongbing (HLB)/Citrus Greening Disease. http://www.freshfromflorida.com/Divisions-Offices/PlantIndustry/Pests-Diseases/Citrus-Health-Response-Program/HLB-Citrus-Greening. Accessed 2014 March 12. 13. Hodges AW, Spreen TH (2012) Economic Impacts of Citrus Greening (HLB) in Florida, 2006/07–2010/ 11. FE 903 http://edis.ifas.ufl.edu/pdffiles/FE/FE90300.pdf. Accessed 2014 March 12. 14. French JV, Kahlke CJ, da Grac¸a JV (2001) First record of the Asian citrus psylla, Diaphorina citri Kuwayama (Homoptera: Psyllidae), in Texas. Subtropical Plant Science 53: 14–15 (2001). 15. (FDQO-CG-ACP) (2009) Federal Domestic Quarantine Order, Citrus greening and Asian citrus psyllid. http://www.aphis.usda.gov/plant_health/plant_pest_info/citrus_greening/downloads/pdf_files/spro/ federalorder09-21-09.pdf. 16. Knapp JL, Albrigo LG, Browning HW, Bullock RC, Heppner JB, et al. (1995) Citrus Leafminer, Phyllocnistis citrella Stainton: Current Status in Florida 1995. Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL. 17. Hall DG, Albrigo LG (2007) Estimating the relative abundance of flush shoots in citrus with implications on monitoring insects associated with flush. HortSci 42: 364–368. 18. Qureshi JA, Stansly PA (2008) Rate, placement and timing of aldicarb applications to control Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), in oranges. Pest Manag Sci 64: 1159– 1169. 19. McCoy CW (1985) Citrus: current status of biological control in Florida. In: Hoy, M.A., Herzog, D.C. (Eds.), Biological Control in Agricultural IPM Systems. Academic, Orlando, FL, pp. 481–499. 20. Vanden Berg MA, Dippenaar-Shoeman AS, Deacon VE, Anderson SH (1992) Interactions between citrus psylla, Trioza erytreae (Hemiptera: Triozidae) and spiders in an unsprayed citrus orchard in the Transvaal Lowveld. Entomophaga 37: 599–608. 21. Michaud JP (2004) Natural mortality of Asian citrus psyllid (Homoptera: Psyllidae) in central Florida. BiolCont 29: 260–269.
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December 1, 2014
19 / 22
Management of Diaphorina citri
22. Qureshi JA, Stansly PA (2009) Exclusion techniques reveal significant biotic mortality suffered by Asian citrus psyllid Diaphorina citri (Hemiptera: Psyllidae) populations in Florida citrus. Biol Cont 50: 129–136. 23. Qureshi JA, Stansly PA (2010) Dormant season foliar sprays of broad spectrum insecticides: An effective component of integrated management for Diaphorina citri (Hemiptera: Psyllidae) in citrus orchards. Crop Prot 29: 860–866. 24. Hoy MA, Nguyen R (2001) Classical biological control of Asian citrus psylla. Citrus Indust 81: 48–50. 25. Qureshi JA, Stansly PA (2010) Tamarixia radiata Waterston [Hymenoptera: Eulophidae], an ectoparasitoid of Diaphorina citri Kuwayama [Hemiptera: Psyllidae]: http://www.nysaes.cornell.edu/ent/ biocontrol/parasitoids/Tamarixia.html. Accessed 2014 March 12. 26. Qureshi JA, Stansly PA (2011) Three homopteran pests of citrus as prey for the convergent lady beetle Hippodamia convergens: suitability and preference. Environ Entomol 40: 1503–1510. 27. Qureshi JA, Kostyk BC, Stansly PA (2011) Effectiveness of selective insecticides to control Asian citrus psyllid and citrus leafminer during leaf flushing. Proc Fla State Hort Soc 124: 85–89. 28. Stansly PA, Arevalo HA, Zekri M, Hamel R (2009) Cooperative dormant spray program against Asian citrus psyllid in SW Florida. Citrus Indust 90: 14–15. 29. Rogers ME (2008) General pest management considerations. Citrus Indust 89: 12–17. 30. Rogers ME, Stansly PA, Stelinski LL (2012) Florida Citrus Pest Management Guide: Asian Citrus Psyllid and Citrus Leafminer. Entomol. Nematol. Dept., Fla. Coop. Ext.Serv.,Inst.FoodAgri.Sci.,Univer.Fla. http://edis.ifas.ufl.edu/in686/ENY734. 31. Jackson LK (1999) Citrus growing in Florida. Univ. Fla. Press, Gainesville. 32. SAS for Windows (2004) Version 9.1. SAS Institute, Cary, NC. 33. Qureshi JA, Stansly PA (2007) Integrated approaches for managing the Asian citrus psyllid Diaphorina citri (Homoptera: Psyllidae) in Florida. Proc Fla State Hort Soc 120: 110–115. 34. Stansly PA, Qureshi JA, Kostyk BC (2011) Foliar insecticides for control of Asian citrus psyllid and citrus leafminer on oranges, spring, 2010. Arthrop. Manag. Tests 36: doi: 10.4182/amt.2011.D14. 35. Stansly PA, Kostyk BC (2012) Insecticidal control of Asian citrus psyllid with tolfenpyrad pyrifluquinazon, and spirotetramat, 2011. Arthrop. Manag. Tests 37: doi: 10.4182/amt.2012.D16. 36. Stansly PA, Qureshi JA (2007) Insecticidal control of Asian citrus psyllid through foliar applications on orange, 2006. Arthrop. Manag. Tests 32: D10. 37. Stansly PA, Qureshi JA, Kostyk BC (2011) Foliar applications of BYI02960 compared to commonly used insecticides for control of Asian citrus psyllid and citrus leafminer in oranges: summer 2010. Arthrop Manag Tests 36: doi: 10.4182/amt.2011.D15. 38. Stansly PA, Qureshi JA, Kostyk BC (2012) Foliar applications of sulfoxaflor, byi02960, and some commonly used insecticides for control of Asian citrus psyllid and citrus leafminer in oranges: summer, 2011. Arthrop Manag Tests 37: doi: 10.4182/amt.2012.D7. 39. Stansly PA, Qureshi JA, Kostyk BC (2009) Control of Asian citrus psyllid and citrus leafminer with foliar applications of insecticides in oranges during summer 2008. Arthrop Manag Tests 34: doi:10.4182/ amt.2009.D12. 40. Stansly PA, Qureshi JA, Kostyk BC (2010) Foliar insecticides against Asian citrus psyllid and citrus leafminer in oranges, 2009. Arthrop Manag Tests 35: doi:10.4182/amt.2010.D10. 41. Stansly PA, Qureshi JA, Kostyk BC (2011) Effect of spray volume and sprayer type on efficacy of insecticides for control of Asian citrus psyllid and citrus leafminer on oranges, 2010. Arthrop Manag Tests 36: doi: 10.4182/amt.2011.D16. 42. Stansly PA, Qureshi JA, Kostyk BC (2012) Comparison of spirotetramat at different spray volumes to some standard insecticides at low volume for control of Asian citrus psyllid and citrus leafminer on oranges: 2011. Arthrop Manag Tests 37: doi: 10.4182/amt.2012.D14. 43. Stansly PA, Qureshi JA, Kostyk BC (2008) Spray applications of insecticides to control Asian citrus psyllid and citrus leafminer on orange, 2007. Arthrop Manag Tests 33: D12. 44. Stansly PA, Qureshi JA, Kostyk BC (2010) Efficacy of foliar applications against Asian citrus psyllid and citrus leafminer in oranges summer, 2009. Arthrop Manag Tests 35: doi:10.4182/amt.2010.D8.
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Management of Diaphorina citri
45. Stansly PA, Qureshi JA, Kostyk BC (2012) Evaluation of experimental and commonly used insecticides for control of Asian citrus psyllid and citrus leafminer in oranges: summer, 2011. Arthrop Manag Tests 37: doi: 10.4182/amt.2012.D9. 46. Stansly PA, Qureshi JA, Kostyk BC (2009) Foliar applications of insecticides against Asian citrus psyllid in oranges, summer, 2008. Arthrop Manag Tests 34: doi:10.4182/amt.2009.D9. 47. Stansly PA, Qureshi JA, Kostyk BC (2008) Sprays of guava leaf extract and insecticides to control Asian citrus psyllid and citrus leafminer on orange, 2007. Arthrop Manag Tests 33: D13. 48. Stansly PA, Qureshi JA, Kostyk BC (2009) Foliar applications of spinetoram compared to commonly used insecticides for control of Asian citrus psyllid and citrus leafminer in oranges, 2008. Arthrop Manag Tests 34: doi:10.4182/amt.2009.D8. 49. Stansly PA, Qureshi JA, Kostyk BC (2010) Foliar applications of insecticides for control of Asian citrus psyllid in oranges during bloom, 2009. Arthrop Manag Tests 35: doi:10.4182/amt.2010.D7. 50. Stansly PA, Qureshi JA, Kostyk BC (2010) Foliar applications of some selective insecticides to suppress Asian citrus psyllid and citrus leafminer in oranges, 2009. Arthrop Manag Tests 35: doi:10.4182/amt.2010. D9. 51. Stansly PA, Qureshi JA, Kostyk BC (2008) Control of Asian citrus psyllid and citrus leafminer on orange with spray applications of insecticide, 2007. Arthrop Manag Tests 33: D11. 52. Stansly PA, Qureshi JA, Kostyk BC (2012) Broad-spectrum foliar sprays for control of Asian citrus psyllid and citrus leafminer in oranges: spring, 2011. Arthrop Manag Tests 37: doi: 10.4182/amt.2012.D8. 53. Stansly PA, Qureshi JA (2007) Evaluations of two foliar insecticides for control of Asian citrus psyllid on orange, 2006. Arthrop Manag Tests 32: D11. 54. Stansly PA, Qureshi JA, Kostyk BC (2009) Control of Asian citrus psyllid with foliar applications of insecticides in oranges during bloom, 2008. Arthrop Manag Tests 34: doi:10.4182/amt.2009.D13. 55. Stansly PA, Qureshi JA, Kostyk BC (2013) Evaluation of three application rates of fenpyroximate and tolfenpyrad against Asian citrus psyllid and citrus leafminer in oranges: fall, 2012. Arthrop Manag Tests 38: doi: 10.4182/amt.2013.D9. 56. Stansly PA, Qureshi JA, Kostyk BC (2013) Foliar sprays of new and labeled insecticides for control of Asian citrus psyllid and citrus leafminer in oranges: summer, 2012. Arthrop Manag Tests 38: doi: 10.4182/amt.2013.D12. 57. Stansly PA, Qureshi JA, Kostyk BC (2013) Asian citrus psyllid and citrus leafminer control in oranges with labeled and experimental insecticides: summer, 2012. Arthrop Manag Tests 38: doi: 10.4182/ amt.2013.D10. 58. Stansly PA, Qureshi JA, Kostyk BC (2013) Foliar sprays of microbial insecticides to control Asian citrus psyllid and citrus leafminer in oranges: summer, 2012. Arthrop Manag Tests 38: doi: 10.4182/ amt.2013.D11. 59. Stansly PA, Qureshi JA, Kostyk BC (2014) Evaluation of Delegate and Closer with different adjuvants for control of Asian citrus psyllid and citrus leafminer in oranges: Summer, 2013. Arthrop Manag Tests 39: doi: 10.4182/amt.2014. 60. Stansly PA, Qureshi JA, Kostyk BC (2014) Rates and volumes of Closer compared to Voliam Flexi, AgriFlex and Fulfill for control of Asian citrus psyllid and citrus leafminer, fall, 2013. Arthrop Manag Tests 39: doi: 10.4182/amt.2014. 61. Stansly PA, Qureshi JA, Kostyk BC (2014) Foliar sprays of GWN 1708 and Sivanto 200 SL for control of Asian citrus psyllid and citrus leafminer in oranges: Summer, 2013. Arthrop Manag Tests 39: doi: 10.4182/amt.2014. 62. Stansly PA, Qureshi JA, Kostyk BC (2014) Low volume and standard spray applications of experimental and labeled insecticides against Asian citrus psyllid on oranges: spring, 2013. Arthrop Manag Tests 39: doi: 10.4182/amt.2014. 63. Stansly PA, Qureshi JA, Kostyk BC (2014) Evaluation of organic insecticides for control of Asian citrus psyllid: Summer, 2013. Arthrop Manag Tests 39: doi: 10.4182/amt.2014. 64. Stansly PA, Kostyk BC (2011) Soil applied insecticidal control of Asian citrus psyllid, 2009. Arthrop Manag Tests 36: doi: 10.4182/amt.2011.D4.
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65. Stansly PA, Kostyk BC (2012) Soil applied insecticidal control of Asian citrus psyllid and citrus leafminer, 2010. Arthrop Manag Tests 37: doi: 10.4182/amt.2012.D15. 66. Stansly PA, Kostyk BC, Huffman M (2009) Persistence of liquid and granular slow release formulations of soil applied insecticides for Asian citrus psyllid control, 2007. Arthrop Manag Tests 34: doi: 10.4182/ amt.2009.D11. 67. Stansly PA, Kostyk BC, Huffman M (2009) Persistence of standard and slow release soil application of imidacloprid for citrus psyllid control, 2007. Arthrop Manag Tests 34: doi: 10.4182/amt.2009.D10. 68. Stansly PA, Kostyk BC (2013) Asian citrus psyllid and citrus leafminer control with systemic insecticides applied by soil drench, 2012. Arthrop Manag Tests 38: doi: 10.4182/amt.2013.D14. 69. Stansly PA, Kostyk BC (2009) Soil applied insecticidal control of Asian citrus psyllid and citrus leafminer, 2008. Arthrop Manag Tests 34: doi: 10.4182/amt.2009.D2. 70. Stansly P A, Kostyk BC, Qureshi JA (2008) Soil applied insecticidal control of Asian citrus psyllid and citrus leafminer, 2007. Arthrop Manag Tests 33: D10. 71. Stansly PA, Jackson KA (2006) Soil applied insecticidal control of Asian citrus psyllid and citrus leafminer, 2005. Arthrop Manag Tests 31: D19. 72. Stansly PA, Kostyk BC (2012) Soil applied insecticidal control of Asian citrus psyllid and citrus leafminer, 2011. Arthrop Manag Tests 37: doi: 10.4182/amt.2012.D10. 73. Croxton S, Stansly TL, Stansly PA (2012) Timing of Temik and Movento applications for control of Asian citrus psyllid (ACP) Diaphorina citri, 2010. Arthrop Manag Tests 37: doi: 10.4182/amt.2012.D1. 74. Stansly PA, Kostyk BC (2013) Soil drench applications for control of Asian citrus psyllid and citrus leafminer, 2012. Arthrop Manag Tests 38: doi: 10.4182/amt.2013.D15. 75. Stansly PA, Kostyk BC (2014) Soil drench applications of insecticides for control of Asian citrus psyllid and citrus leafminer, 2013. Arthrop Manag Tests 39: doi: 10.4182/amt.2014. 76. Tiwari S, Mann RS, Rogers ME, Stelinski LL (2011) Insecticide resistance in field populations of Asian citrus psyllid in Florida. Pest Manag Sci 67: 1258–1268. 77. Tiwari S, Stelinski LL (2013) Effects of cyantraniliprole, a novel anthranilic diamide insecticide, against Asian citrus psyllid under laboratory and field conditions. Pest Manag Sci 69: 1066–1072. 78. Foster SP, Denholm I, Rison J, Portillo HE, Margaritopoulis J, et al. (2012) Susceptibility of standard clones and European field populations of the green peach aphid, Myzus persicae, and the cotton aphid, Aphis gossypii (Hemiptera: Aphididae), to the novel anthranilic diamide insecticide cyantraniliprole. Pest Manag Sci 68: 629–633. 79. Qureshi JA, Khan AA, Jones M, Stansly PA (2013) Management of Asian citrus psyllid in organic citrus groves. Citrus Indust. 94 (2): 6–10. 80. Stansly PA, Arevalo HA, Qureshi JA, Jones M, Hendricks K, et al. (2013) Vector control and foliar nutrition to maintain economic sustainability of bearing citrus in Florida groves affected by huanglongbing. Pest Manag Sci DOI 10.1002/ps.3577. 81. Belasque J, Bassanezi RB, Yamamoto PT, Ayres AJ, Tachibana A, et al. (2010) Lessons from huanglongbing management in Sa˜o Paulo state, Brazil. Journal Plant Path, 92: 285–302. 82. Qureshi JA, Rohrig E, Stansly PA (2012) Introduction and augmentation of natural enemies for management of Asian citrus psyllid and HLB. Citrus Indust. 93 (6): 14–16. 83. Qureshi JA, Kostyk BC, Stansly PA (2009) Control of Diaphorina citri (Hemiptera: Psyllidae) with foliar and soil-applied insecticides. Proc Fla State Hort Soc 122: 189–193. 84. Hall DG, Nguyen R (2010) Toxicity of pesticides to Tamarixia radiata, a parasitoid of the Asian citrus psyllid. BioControl 55: 601–611.
PLOS ONE | DOI:10.1371/journal.pone.0112331
December 1, 2014
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